INT69 Y Diagnose

The compressor protection INT69 Y Diagnose is a further development of the reliable KRIWAN motor protectors. Additional inputs for the phase monitoring as well as supplementary flexible-response protective functions help to improve the availability and extend the service life of a refrigeration system.

The INT69 Y Diagnose automatically saves operational and error data in a non-volatile memory. This data can be retrieved on a PC and analysed for diagnosis. The full scope of the diagnosis is achieved by using a KRIWAN-specific AMS sensor.

This motor protector is mainly employed on compressors of which the motor's direction of rotation is essential for the function.

Functional description

The temperature monitoring of the motor winding is done with two evaluation processes:

• Static: Switch-off is immediate if the nominal response temperature of the built-in AMS or PTC sensors is reached.

• Dynamic: If the temperature increases unusually quickly, the motor is switched off immediately even if the temperature is still far below the nominal response temperature. This prevents excess temperatures from occurring.

A short circuit at an AMS or PTC input also leads to a switch-off. A short cycling leads to a reset delay. After cooldown or elimination of the error and a subsequent reset delay, the compressor can be restarted; restarting after locking only after reset.

The phase monitoring of the motor voltage is active 1s after the start of the motor. The correct phase sequence is monitored for 5s, the phase failure is monitored for the total motor running time. If a wrong phase sequence is detected or there is a phase failure, the motor protector willlock switch off.

After motor stop, the phase monitoring is deactivated for approx. 20s to prevent unintended locking due to brief reverse running of the compressor. For operation in the specified manner, the supply voltage has to be on permanently on the INT69 Y Diagnose. The built-in LED signals the current status of the motor protector (see flash code).